Heretofore, in the agricultural/horticultural field, insecticides or acaricides intended to control various pests are used in practice. However, conventional general-purpose insecticides or acaricides are not always satisfied in terms of efficacy, spectrum, residual effectiveness, etc. As well, the societal requirements such as reduction in the number of applications or the rate of application are not sufficiently fulfilled.
In addition, appearance of pests having gained resistance to conventional general-purpose insecticides or acaricides also becomes a problem. For example, in the cultivation of vegetables, fruit trees, ornamental flowers, teas, wheat/barley, etc., it is becoming difficult to control pests having gained resistance to insecticides or acaricides of various systems, for example, organophosphorus agents (e.g., fenitrothion, malathion, prothiofos, DDVP) and pyrethroid-based (e.g., permethrin, cypermerin, fenvalerate, cyhalothrin), benzoylurea-based (e.g., diflubenzuron, teflubenzuron, chlorfluazuron) and nereistoxin-based (e.g., cartap, bensultap) insecticides or acaricides.
Furthermore, although there are insecticides or acaricides to which pests have not yet gained resistance (for example, organic halogen-based agrochemicals such as DDT and BHC, and chlorinated cyclic diene-based agrochemicals such as aldrin, dieldrin, endrin, heptachlor and benzoepin), these are disadvantageous in view of toxicity, environmental pollution, etc. Accordingly, it is keenly demanded to develop a novel insecticide or acaricide exhibiting a sufficient control effect with a small dosage also on various pests having gained resistance to agricultural/horticultural insecticides or acaricides that have been conventionally used for general purposes.
As to a 1,2,3-triazole derivative exhibiting an insecticidal or acaricidal activity, for example, Patent Document 1 describes a 1,2,3-triazole derivative having an insecticidal or acaricidal activity against various pests but discloses none of the 1,2,3-triazole derivative according to the present invention. In addition, although a compound analogous to the present invention is described in Patent Documents 2 to 18, there is absolutely no description of the 1,2,3-triazole derivative of the present invention in which the 1,2,3-triazole ring is substituted at the 1-position with a 2-alkyl thio group, a 2-alkylsulfinyl group or a 2-alkylsulfonyl group and substituted with a phenyl group that may be substituted with other substituent.